A protester is hit by a water cannon during clashes in Taksim Square, Istanbul, on Tuesday. Police used water cannons and tear gas as they moved into the square, where two weeks of protests have been held.

The day began with a warning from Turkish Prime Minister Recep Tayyip Erdogan that his patience with protesters who were gathered in his country’s commercial and symbolic capital had run out.

Hours later, as dusk descended over Istanbul, there was bedlam as police armed with water cannons and shields, tear gas and rubber bullets, spread out across Taksim Square and drove as many as 100,000 demonstrators from the park.

Gezi Park in Taksim Square, where the government planned to pave over a grove of sycamores to make way for a new mall, has become a line in the sand for protesters. They have occupied a tent city in the park for weeks, chanting, “Istanbul is ours, Taksim is ours.”

“Almost a stampede right now in Taksim,” freelance photographer Monique Jaques wrote on Twitter Tuesday evening. “Police fired directly into the crowd. Massive amounts of tear gas.”

Some protesters set fire to a police van with a Molotov cocktail, while others climbed barricades, waving a flag depicting jailed Kurdish rebel leader Abdullah Ocalan.

Human Rights Watch deputy executive director Carroll Bogert wrote on Twitter that an emergency room in a hospital near Taksim was filled with tear gas, “doctors’ eyes streaming.”

It was an amazing contrast to the scene earlier in the park, where protesters had spent much of the day dancing and playing music, munching on kebabs and watermelon.

Yet amid the carnival atmosphere was the awareness that things could unravel in a moment. Local media reported protesters wrote their blood type on their arms as a precaution.

Violence has also flared in dozens of other cities around the country, notably in Izmir and the capital, Ankara. Four people have been killed, including a police officer, the Associated Press reported, and about 5,000 have been treated for injuries or the effects of tear gas, according to the Turkish Human Rights Foundation.

Much of the analysis around the protests has framed them as an uprising of secular Turks who fear that Erdogan is “Islamicizing” the country, with a crackdown on alcohol sales among his recent moves.

But Ariel Salzmann, a Queen’s University associate professor and Turkey expert, said the unrest points to a Vladimir Putin-style power grab by Erdogan.

“We get totally blinded by this Islam factor and by the so-called clash of cultures,” Salzmann said. “What Erdogan is trying to do is create another Russia where he is in the role of Putin. That’s what Turkey is headed towards becoming.”

Unrest has been simmering in Turkey since at least November, when Erdogan took a step toward extending his powers with a proposal by his Islamist-rooted AK Party to set up a presidential system.

Currently, Turkey’s president is a largely ceremonial figure. But Erdogan, who presented himself as a champion of democracy during the Arab Spring uprisings, wants to create an executive presidency within the framework of a new constitution.

Jordan’s King Abdullah, Salzmann said, has been quoted as saying that Erdogan sees democracy as a “bus.”

“You ride it until you get in power and then you get off,” Salzmann said.

The protests can’t be compared to the Arab Spring either, says Henri Barkey, a professor of international relations at Lehigh University and a Turkey expert.

“The Arab Spring was about fighting back against a regime,” Barkey said in a phone interview from New York. “Those people wanted to change a system. Nobody in Turkey wants to change the democracy and go back to a military government.”

Erdogan, a former mayor of Istanbul, remains popular in much of the country. As many as 62 per cent of Turks say they have a favourable view of the prime minister, according to a Pew Research Center poll taken in March. He has cleaned up streets, improved public services and reduced corruption, Barkey said.

“Erdogan is a world leader who took us from the bottom to where we are today,” Ankara municipal worker Ali Gunes said in an interview with Bloomberg. “If the prime minister says ‘die,’ we’ll die, and if he lets us, we’ll make the provocateurs pay.”

The crackdown Tuesday came after a warning from Erdogan in the morning.

“To those who . . . are at Taksim and elsewhere taking part in the demonstrations with sincere feelings, I call on you to leave those places and to end these incidents, and I send you my love,” Erdogan said in a televised address, the Associated Press reported. “But for those who want to continue with the incidents I say: It’s over.

“Not only will we end the actions, we will be at the necks of the provocateurs and terrorists, and no one will get away with it.”

Human rights watchdog Amnesty International said 72 lawyers were arrested Tuesday as they gathered at Istanbul’s main courthouse to make a statement about the situation in Gezi Park.

Analysts have said protesters in Turkey cut across age, religion and class lines. Some condemn the country’s urban development projects, such as a new bridge over the Bosphorus River that will mean clear-cutting thousands of trees, and be named after a divisive historical figure. Some protesters are members of the Alevi minority, who say the state and Sunni majority discriminate against them.

Liberals are angry that Turkey has jailed more journalists than any other country. The Committee to Protect Journalists said in December that 49 Turkish journalists were behind bars. By contrast, the committee said China had jailed 32 journalists.

Critics also argue that judicial reforms passed in 2010 give the Turkish government too much influence over the appointment of judges.

“If there was an election tomorrow Erdogan would win,” Barkey said. “But that doesn’t mean that he’s not making mistakes and that he’s not being autocratic. He’s a micromanager. Everything has to be decided by him. He doesn’t listen to people because he doesn’t have to.”

While Erdogan was scheduled to meet Wednesday with some of the protesters, it has become apparent in recent days that the demonstration at Taksim Park could end in violence.

On Sunday, Erdogan gave six fiery speeches at rallies, insisting that his planned development project at the park would proceed. The Hurriyet Daily News quoted him as saying: “We are going to show patience, but patience has a limit as well.”